This study examined the validity, reliability, and discriminatory capacity of the gallon-jug shelf-transfer (GJST) test. Six hundred fifty-three independent-living older adults (463 women age 72.9 +/- 7.0 years, 190 men age 74.3 +/- 6.7 years) participated. Participants moved five 1-gallon jugs (approximately 3.9 kg) from a knee-high to a shoulder-high shelf as quickly as possible. The GJST showed an exponential performance decline with age, and there were significant correlations between the GJST and common functional tests (p<.001). High within-day and between-days reliability was detected. The test also detected differences resulting from training status (p<.01) and training protocols (p<.05). The GJST is a valid, reliable, inexpensive, safe, and easily administered clinical test for identifying physically vulnerable elders who could benefit from interventions such as exercise to improve their physical capacities and maintain independence.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill.
Purpose:Previously it has been observed that, in well-trained 800-m athletes, VO2max is not attained during middle-distance running events on a treadmill, even when a race-type pacing strategy is adopted. Therefore, the authors investigated whether specialization in a particular running distance (400-m or 800-m) influences the VO2 attained during running on a treadmill.Methods:Six 400-m and six 800-m running specialists participated in the study. A 400-m trial and a progressive test to determine VO2max were completed in a counterbalanced order. Oxygen uptakes attained during the 400-m trial were compared to examine the influence of specialist event.Results:A VO2 plateau was observed in all participants for the progressive test, demonstrating the attainment of VO2max. The VO2max values were 56.2 ± 4.7 and 69.3 ± 4.5 mL · kg−1 · min−1 for the 400-m- and 800-m-event specialists, respectively (P = .0003). Durations for the 400-m trial were 55.1 ± 4.2 s and 55.8 ± 2.3 s for the 400-m- and 800-m-event specialists, respectively. The VO2 responses achieved were 93.1% ± 2.0% and 85.7% ± 3.0% VO2max for the 400-m- and 800-m-event specialists, respectively (P = .001).Conclusions:These results demonstrate that specialist running events do appear to influence the percentage of VO2max achieved in the 400-m trial, with the 800-m specialists attaining a lower percentage of VO2max than the 400-m specialists. The 400-m specialists appear to compensate for a lower VO2max by attaining a higher percentage VO2max during a 400-m trial.
Previous investigations have revealed that in well-trained middle-distance runners, oxygen uptake (VO 2 ) does not attain maximal values (VO 2max ) in exhaustive treadmill trials where the VO 2 demand exceeds VO 2max . To date, this shortfall in the VO 2 attained has been demonstrated in trials as short as 2 min in duration. In this study, we investigated whether a reduction in exhaustive test duration influences the VO 2 attained during running on a treadmill. Six middle-distance runners participated in the study, completing an exhaustive 400 m and 800 m trial. These trials, together with a progressive test to determine VO 2max , were completed in a counterbalanced order. Oxygen uptakes attained during the 400 m and 800 m trials were compared to examine the influence of exhaustive test duration. A plateau in VO 2 was observed in all participants for the progressive test, demonstrating the attainment of VO 2max . The mean speed, duration, and resulting distance in the constant-speed exhaustive trials were 25.8 km × h (1 (s01.2), 55.8 s (s 02.3), and 400.2 m (s 020.2) for the 400 m trial, and 24.3 km × h (1 (s00.8), 108.4 s (s 021.2), and 730.1 m (s0129.1) for the 800 m trial, respectively. A paired-samples t-test revealed a significantly different (P00.018)%VO 2max was attained for the 400 m (85.7%, s 03.0) and 800 m (89.1%, s05.0) trials. In conclusion, VO 2 did not reach VO 2max during the exhaustive constant-speed 400 m and 800 m trials, but the test duration does influence the%VO 2max achieved. Specifically, the VO 2 attained becomes progressively further below VO 2max as trial duration is reduced, such that 89% and 86% VO 2max is achieved in exhaustive 800 m and 400 m constant-speed trials, respectively.
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